1. Field of the Invention
This invention relates generally to work clamps and more particularly to a novel self-aligning work holding clamp.
2. Prior Art
A variety of machine shop, fabrication, assembly, and other operations require clamping of work parts to a work support on which each part rests. A vast assortment of work holding clamps for this purpose have been devised.
This invention is concerned with a problem which is encountered in certain work clamping applications. The applications referred to are those in which the work parts have a particular portion, referred to herein as a gripping element, for engagement by a work holding clamp. For one reason or another, such as dimensional differences between parts, differences in the placement of the parts on the work support, or structural difference between the parts, the position of the gripping elements of the parts relative to the work support may vary slightly from part to part. This slight variation from part to part in the positions of their gripping elements presents a problem with regard to clamping of the parts to the work support.
Consider, for example, the use of a work holding clamp with a jaw fixed to the work support. Unless the gripping element of each part happens to be precisely located in firm contact with the fixed clamp jaw, closure of the clamp will either result in improper clamping of the part or in movement of the part relative to the support due to forcing of the gripping element against the fixed jaw by the closing movable jaw.
The above disadvantages of using a work holding clamp with a fixed jaw could be avoided, of course, by precise placement of each work part on the work support so that its gripping element is properly located relative to the fixed jaw. Such precise placement of each part, however, at best would be tedious and time consuming and may be impossible owing to the necessity of locating the parts relative to some other reference.
Another way of resolving the basic work clamping problem under discussion is to use a work holding clamp which is bodily adjustable relative to the work support to permit accommodation of the clamp to the work part. That is to say, this method of resolving the work clamping problem involves accommodating the variations, from part to part, in the positions of their gripping elements relative to the work support by shifting the clamp relative to the work support to the proper clamping position for each part. This solution to the problem, however, is also tedious and time consuming.